JPH0317066B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a clad container.

Conventionally, containers made of Mo or Mo alloys have been widely used in crucibles for melting ores containing high-temperature glass and metal oxides, trays for vacuum deposition, boats, etc. This is because Mo has a very high melting point of approximately 2610°C and is highly ductile and malleable, making it easy to process. However, when the temperature exceeds 500°C, Mo reacts with oxygen in the air to form an oxide, and this oxide easily evaporates, making it difficult to use it in an inert atmosphere. Furthermore, even when used in such an inert atmosphere, when melting glass or ore containing metal oxides, or metals or alloys containing oxygen, the oxygen contained in the melt and the
The drawback was that Mo combined to form oxides and Mo eluted from the container, shortening the life of the container. For this reason, attempts have been made to improve wear resistance by adding other metals to the alloy, but the reality is that no alloy has been discovered that is sufficient to prevent Mo from oxidizing.

The present invention has been made in view of the above drawbacks,
The purpose is to provide a long-life container with excellent wear resistance.

The present invention is a clad container characterized in that the surface of Mo or Mo alloy is coated with Ir or Ir alloy.

In the present invention, Ir or Ir alloy is used because
This is because the melting point of Ir is 2454°C, which is as high as Mo, and it also has excellent oxidation resistance at high temperatures, especially against metal oxides. However, it was difficult to process Ir or Ir alloy into plates, so we decided to cover it. For coating, physical vapor deposition such as ion plating, sputtering or vapor deposition is better than wet plating. This is because physical vapor deposition allows Ir atoms to be buried in the surface layer of the Mo container, resulting in good compatibility between Mo and Ir atoms, resulting in a high adhesion hardness at the joint surface of the Ir-Mo alloy, resulting in high mechanical strength. This is because a clad container can be obtained. In this way, a crucible coated with Ir or an Ir alloy has excellent oxidation resistance and mechanical strength, so it has a long life. Note that Ir alloys include Ir-Mo, Ir-W, and the like.

Examples and conventional examples will be described below.

Example 1 Ir was applied to a thickness of 10 μm on the inner wall of a U-shaped Mo crucible with a wall thickness of 5 mm, a height of 100 mm, and an inner diameter of 80 mm under the following conditions.
Ion plating was performed up to.

Pressure: Ar gas 2.0×10 ^-4 mmHg Voltage: 400V Current: 1A Electron beam melting: 9kV, 300mA Thermal electron: 10V, 100A This is referred to as Implementation Product 1.

Example 2 An Ir-W alloy was magnetron sputtered to a thickness of 0.1 mm on the inner and outer walls of a Mo crucible having the same shape as in Example 1 under the following conditions.

Pressure: Ar gas 3×10 ^-3 mmHg Voltage: 400V Current: 1A High frequency power source: 13.56MHz This is implementation product 2.

Conventional Example The Mo crucible used in Example 1 was used as a conventional product.

Next, we added SiO ₂ − to the above implementation products 1 and 2 and the conventional product.
Put 500g of Al ₂ O ₃ glass in Ar atmosphere, temperature about 2200.
It was used at ℃×60 minutes. When this process was repeated 10 times, 60 μm was scraped from the surface of the Mo container with the conventional product, while 5 μm was scraped with product 1 and 5 μm was scraped with product 2.
Only 3μm was removed.

Next, when the bottoms of the containers for products 1 and 2 were directly heated in the atmosphere with a heater and held at a temperature of about 1000°C for 10 hours, Mo in product 1 was oxidized and evaporated.
The weight loss was 12g, whereas the weight loss of Example 2 was not.

The hardness of the surface layer of the conventional product and the hardness of the boundary layer of implemented products 1 and 2 are 150Hv, 250Hv, and 300Hv, respectively.
It was hot.

From these facts, the clad crucible of the present invention has significantly superior oxidation resistance as a crucible for dissolving metal oxides compared to conventional products, and in addition, Example 2, which is coated with Ir alloy up to the outer wall, has oxidation resistance even when heated in the atmosphere. It turns out that it is excellent. Furthermore, the hardness of the boundary layer of the implemented product is much higher than the hardness of the surface layer of the conventional product, which indicates that the implemented product has excellent mechanical strength. In particular, product 2 consists of two highly hard Ir-Mo
It can be seen that it has particularly excellent mechanical strength because it has a sandwich structure in which a Mo layer is sandwiched between alloy layers.

As described in detail above, according to the present invention, it is possible to provide a clad container with excellent wear resistance and long life. Moreover, if the Mo container is completely coated, it can have a long life even in the atmosphere, does not require expensive equipment, and requires only a small amount of expensive Ir, making it inexpensive.

Claims (1)

[Claims] 1. A clad container characterized in that the surface of Mo or Mo alloy is coated with Ir or Ir alloy.